Generally speaking, traditional methods for preventing water intrusion include using a silicon gasket that runs along a tongue and groove arrangement on corresponding halves of a casing or enclosure. This arrangement can be found in many handheld devices that might require a certain level of water resistance to protect the internal components of the device. Normally, these devices may include screws for connecting the corresponding top and bottom sections of the casing. The screws maintain a constant pressure for sealing the sections. However, if the top and bottom sections of the casing include a more complicated profile, such as with free-form sections, the screws do not provide constant pressure, because the screws can only provide pressure in one direction.
FIG. 1 is a perspective view of a casing 10 or housing, which incorporates a conventional sealing assembly for sealing a first section 12 of the casing 10 with a second section 14. The first section 12 includes a tongue component 16 and the second section 14 includes a groove component 18. When the tongue component 16 is aligned with the groove component 18, such as when one of the first or second sections 12, 14 is flipped upside down and placed on top of the other section, the tongue and groove arrangement 16, 18 creates a rudimentary sealing arrangement for allowing the casing 10 to provide a certain level of water tightness to protect the interior of the casing 10.
To ensure that the tongue component 16 is maintained within the groove component 18, screws or other hardware (not shown) can be inserted through pairs of holes 20, 22, 24, 26 in each of the first and second sections 12, 14. The pressure applied by the screws or other hardware is intended to keep the first section 12 held against the second section 14.
FIG. 2 is a cross-sectional side view of a portion of the casing 10 shown in FIG. 1, where the tongue component 16 of the first section 12 is aligned with the groove component 18 of the bottom section 14. FIG. 2 further shows a gasket 30 (or washer), which may be used in the conventional sealing assembly for increasing the water resistance of the casing 10. When the screws or other hardware are tightened, a first force, indicated by arrow 32, is applied on the first section 12 in a downward direction and a second force, as indicated by arrow 34, is applied on the second section 14 in an upward direction. Also, the forces 32, 34 may compress the gasket 30 to optimize its sealing effectiveness. Since the pairs of holes 20, 22, 24, 26 for the screws are oriented in a substantially vertical orientation, the forces 32, 34 will consequently be applied vertically as well.
FIG. 3 schematically depicts a perspective view of a gasket 40 used in another conventional sealing assembly having a more complex free-form profile. In this illustration, only a bottom portion 42 of a casing is shown, but it should be noted that an upper portion having a corresponding profile may be used with the bottom portion 42.
The upper rim 44 of the bottom portion 42 of the casing includes a non-planar surface, which may be common in many conventional casings having such a free-form profile. If downward and upward forces 32, 34 (FIG. 2) are applied to the casing of FIG. 3, the forces 32, 34 will not be uniform on each portion of the gasket 40, since the gasket 40 will be pressed at an angle with respect to the rim 44 having the non-uniform profile.
The horizontal portions of the rim 44 will enable the gasket 40 to be pressed evenly, such as at locations 46 and 48. However, the gasket 40 would need to be pressed at an angle, such as at locations 50 and 52, to correspond to the orientation of the rim 44 at those locations 50, 52. However, as mentioned above, the screws or other hardware are only configured to provide up and down forces and are unable to provide forces at the angles indicated by the arrows in locations 50, 52.
Therefore, a need exists for water-resistant sealing assemblies for enabling uniform forces to be applied around a periphery of a free-form casing. Such uniform pressure may help to maintain a constant force on sealing components (even at an angle) and can provide improved sealing functionality.